It was a meeting that had been in the pipeline for well over two months. Adam Werritty, the self-styled "adviser" to the defence secretary, Liam Fox, had met Harvey Boulter, the chief executive of Porton Group, a private equity company early last April, in Dubai where the businessman lived. Boulter wanted a favour. He needed to see Fox to discuss a dispute over a $41m (£26m) payment for healthcare technology.

A friendly email discussion followed. "Very good meeting with you in Dubai," wrote Werritty on 5 April, promising that the matter of the meeting was in hand.

On 16 June, on the eve of the talks, Boulter emailed offering transport for "you and your boss" from the Shangri-La hotel in Dubai where Werritty was staying. Fox preferred to meet in his own hotel in the city. Boulter said the encounter took place at 11am and lasted for 40 minutes.

The email trail leading to the Dubai meeting in June would appear to contradict the version of events suggested by Fox on Saturday, when he claimed that it took place as a result of a chance encounter in a Dubai restaurant.

For the increasingly beleaguered defence chief, the emails uncovered by the Guardian will become the source of yet more questions in Westminster tomorrow.

Fox, the one-time hero of the Tory right, known at Westminster for his plain speaking, name-dropping and none-too-subtle methods of self-promotion, is this weekend fighting for his political survival.

Monday will see the Commons chamber packed with MPs intrigued by the relationship, and the often mysterious movements of Dr Fox.

Labour will be baying for blood – keen to secure the first cabinet scalp since the Liberal Democrat David Laws was pushed into quitting over his expenses claims within weeks of the coalition government being formed last summer.

David Cameron, never close to Fox, of whom he has always been rather wary, will not be quaking in his boots. But he will not want to lose a cabinet minister in the eye of a storm over which he has absolutely no control.

Why, Labour will ask, has Werritty, 16 years Fox's junior and a close friend for a decade and a half, been allowed such access to the defence secretary's discussions with top brass across the world when he is not a government employee and has had no security vetting?

Why did Werritty attend meetings with the secretary of state in London, Sri Lanka and Dubai when he had no official role? How, in relation to the Dubai meeting, can the MoD have claimed it knew nothing of the meeting when the defence secretary has 24-hour security provided by government, watching his every move? Has Fox put national security at risk? What about potential conflicts of interest with his friend's business interests?

Fox's enemies will want to ask questions about Werritty's links to a string of companies that have health and defence interests. In addition to a now-dissolved defence advisory firm, Security Futures, a company that Werritty joined in 2006 and whose directors have included the Tory MP Laura Sandys, he is the sole shareholder in a company called Danscotia Consulting, which lists his occupation as business consultant.

Records show that in February, Werritty set up Todhia Ltd, in which he is the sole director. Neither company lists the nature of its business with Companies House.

Companies House records also reveal that in 2002, when Fox was shadow health secretary and therefore someone who was briefed on market-sensitive policy developments by civil servants, Werritty was appointed director of a company named UK Health Ltd.

Two years later he became director of UK Health Group Ltd, in which both he and Fox became shareholders. The same year he joined the board of another company, UK Health Supply Services Ltd. Both firms have now been dissolved. But their roles are unknown.

For Fox Monday the next 48 hours will be the most critical of his political career since he stood up at the Conservative party conference in Blackpool in 2005 to make his pitch to lead the Tory party – a bid that was ultimately unsuccessful. On that occasion, with David Cameron also in the race to succeed Michael Howard, Fox was typically, breezily confident, delighting the Tory faithful with patriotic and eurosceptic rhetoric that won him a lengthy standing ovation.

On stages across the world, Fox has always been adept at mixing light wit with tub-thumping populist messages. In his Blackpool speech he called for all schools to fly the union flag "as a symbol of what unites us".

He also carefully name-checked the emerging favourite, Cameron. "I play tennis with David Cameron and we're friends, even though he beats me," he said.

To his fellow MPs and ministerial colleagues, Fox's current troubles do not come as that much of a surprise. "He is an odd bloke," said one fellow minister. "He has fingers in so many pies that you kind of think one of them will land him in trouble somewhere along the line."

Another Tory MP said Fox's tendency to name-drop and brag about his close friendships with Republicans in the US, media magnates such as David and Frederick Barclay (owners of the Daily Telegraph), and his endless globe-trotting, even before he entered the cabinet, has made many bristle and help explain why he has plenty of enemies in the Tory party and in Whitehall. "I think you either roll with the bluster or find it repellent," said a Tory MP.

Fox's ability to climb the social and political ladder was exemplified last month when Lady Thatcher made one of her rare appearances in public to attend his 50th birthday party.

Even before Fox entered the cabinet, there were signs that he had got under the skin of diplomats and military figures in other countries as he roved the world talking up what a Tory government could do. Cables released by WikiLeaks reveal that Fox met the US ambassador, Louis Susman, before the general election and Susman recorded: "Liam Fox affirmed his desire to work closely with the US if the Conservative party wins power … 'we [Conservatives] intend to follow a much more pro-American profile in procurement'."

He also ran into trouble with expense claims that he said proved how well connected he was. In June 2009, it emerged he had claimed £19,000 over the previous four years for his mobile phone. Fox said this was due to regular trips overseas, in his capacity as shadow defence secretary.

Fox, who was born and raised in East Kilbride, Scotland, attended the local comprehensive school and then went on to study medicine at Glasgow University. He became president of the University's Conservative and Unionist Association, and in his spare time took a keen interest in debating, winning national and international prizes.

As well as his career in the NHS, he worked as a civilian army medical officer, which enabled him to see army life at first-hand. He entered parliament in 1992 and held a number of junior government posts before becoming a junior foreign office minister in the dying days of the John Major government in 1996. In opposition he occupied the shadow health post and was party chairman from 2003-2005 until he became shadow defence secretary in 2005.

On 10 June 2005, he announced his engagement to longtime girlfriend Dr Jesme Baird, 37, director of patient care at the Roy Castle Lung Cancer Foundation. Before the couple tied the knot he said their marriage should end gossip about his private life. "I think that there are all sorts of smears going around and politicians should stick to issues. If someone accused me of doing something against the law I might feel bound to answer it. Otherwise I would have no comment to make," he told the London Evening Standard.

He has irritated the prime minister on numerous occasions, particularly after MoD leaks about defence cuts, but they have had better relations since Fox has shown strong support for the Libya campaign. On Saturday, No 10 said it had "full confidence" in the defence secretary as the pressure on him mounts.